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1.

001-es BibID:BIBFORM112577
035-os BibID:(WoS)000431833500088 (Scopus)85046700183
Első szerző:Aime, Silvio
Cím:Exploiting the Proton Exchange as an Additional Route to Enhance the Relaxivity of Paramagnetic MRI Contrast Agents / Silvio Aime, Simona Baroni, Daniela Delli Castelli, Ernő Brücher, Istvan Fábián, Sonia Colombo Serra, Alberto Fringuello Mingo, Roberta Napolitano, Luciano Lattuada, Fabio Tedoldi, Zsolt Baranyai
Dátum:2018
ISSN:0020-1669 1520-510X
Megjegyzések:The relaxivity of Gd(HP-DO3A) was studied as a function of pH and buffer composition in order to identify the main factors of the observed relaxation enhancement due to the exchange of the coordinated hydroxyl proton. It was established that the paramagnetic relaxation time, T1M, of the coordinated hydroxyl proton is about 50% shorter than that of the protons in the coordinated water molecule. The control of the pK of the coordinated alcoholic ?OH moiety in the ligand is fundamental to utilize the proton exchange enhanced relaxivity under physio/pathologic conditions. A new derivative of Gd(HP-DO3A) was synthesized by replacing the ?CH3 group with a ?CF3 moiety. In this complex, the ?OH group becomes more acidic. Consequently, the maximum contribution of the proton exchange to the relaxivity is shifted to a lower pH region with the fluorinated ligand.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
relaxivity
MRI
proton exchange
Megjelenés:Inorganic Chemistry. - 57 : 9 (2018), p. 5567-5574. -
További szerzők:Baroni, Simona Castelli, Daniela Delli Brücher Ernő (1935-) (vegyész) Fábián István (1956-) (vegyész) Serra, Sonia Colombo Fringuello Mingo, Alberto Napolitano, Roberta Lattuada, Luciano Tedoldi, Fabio Baranyai Zsolt
Pályázati támogatás:124983
OTKA
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2.

001-es BibID:BIBFORM047932
Első szerző:Baranyai Zsolt (vegyész)
Cím:Equilibrium, Kinetic and Structural Studies of AAZTA Complexes with Ga3+, In3+ and Cu2+ / Zsolt Baranyai, Fulvio Uggeri, Alessandro Maiocchi, Giovanni B. Giovenzana, Camilla Cavallotti, Anett Takács, Imre Tóth, István Bányai, Attila Bényei, Ernő Brücher, Silvio Aime
Dátum:2013
Megjegyzések:A detailed study of the structures, thermodynamic stabilities and kinetics of the dissociation of Ga3+, In3+ and Cu2+ complexes formed with the heptadentate ligand AAZTA is reported. The stability constants (logKML) of the AAZTA complexes of Ga3+, In3+ and Cu2+ are 22.18, 29.58 and 22.27, respectively, which suggests that the seven-membered-ring skeleton is suited to the accommodation of these metal ions. The solid-state structure of Cu(H2AAZTA)]?H2O shows a distorted octahedral coordination. The equatorial coordination sites of Cu2+ are occupied by one of the ring N atoms, a water O atom, one of the carboxylate O atoms and the N atom of the iminodiacetate moiety. The other ring N atom and thecarboxylate O atom of the iminodiacetate moiety coordinate to the Cu2+ in the axial positions. In the pH range 4.5?8.5, Ga3+ is present in the form of the highly stable [Ga(AAZTA)OH]2? (log ?GaLH?1 = 17.69) The exchange reactions of [Ga(AAZTA)OH]2? with Cu2+ and transferrin are very slow and mainly occur through the spontaneous dissociation of the complex close to physiological conditions. The half-life for the dissociation of [Ga(AAZTA)OH]2? is t1/2 = 23 h at pH = 7.5 and 25 ?C in 0.025 M NaHCO3 and 0.15 M NaCl. The high conditional stability, fast formation and sufficiently slow dissociation of [Ga(AAZTA)OH]2? represent promising properties for the complexation and diagnostic applications of radioactive Ga isotopes.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Gallium
Indium
Copper
Complexation
Thermodynamics
Kinetics
Radiopharmaceuticals
Imaging agents
Molekulatudomány
Doktori iskola
Megjelenés:European Journal Of Inorganic Chemistry. - 2013 : 1 (2013), p. 147-162. -
További szerzők:Uggeri, Fulvio Maiocchi, Alessandro (vegyész) Giovenzana, Giovanni Battista Cavallotti, Camilla Takács Anett Tóth Imre (1950-) (vegyész) Bányai István (1953-) (vegyész) Bényei Attila (1962-) (vegyész) Brücher Ernő (1935-) (vegyész) Aime, Silvio
Pályázati támogatás:K-84291
OTKA
TÁMOP-4.2.1/B-09/1/KONV-2010-0007
TÁMOP
Bimodális kontrasztanyagok tervezése, előállítása és komplexeik fizikai-kémiai tulajdonságaik jellemzése
TÁMOP-4.2.2/B-10/1-2010-0024
TÁMOP
Kémiai Tudományok Doktori Iskola
EU COST (TD1004) "Theragnostics Imaging and Therapy" Action Program.
Egyéb
HU11MO2-TET_10-1-2011-0202
Egyéb
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3.

001-es BibID:BIBFORM016454
Első szerző:Baranyai Zsolt (vegyész)
Cím:Equilibrium Studies on the Gd3+, Cu2+ and Zn2+ Complexes of BOPTA, DTPA and DTPA-BMA Ligands: Kinetics of Metal-Exchange Reactions of Gd(BOPTA) (2-) / Zsolt Baranyai, Zoltán Pálinkás, Fulvio Uggeri, Ernő Brücher
Dátum:2010
ISSN:1434-1948
Megjegyzések:The stability and protonation constants of the complexes formed between the ligand BOPTA [H(5)BOPTA: 4-carboxy-5,8,11-tris(carboxymethyl)-1-phenyl-2-oxa-5,8,11-triazatrideca n-13-oic acid] and Gd3+, Cu2+, and Zn2+ have been determined by pH potentiometry (Gd3+, Zn2+) and spectrophotometry (Cu2+) at 25 degrees C and at constant ionic strength maintained by 0.15 M NaCl. For comparison, the stability and protonation constants of the complexes of Gd3+, Cu2+, and Zn2+ formed with DTPA and DTPA-BMA {H(5)DTPA: diethylenetriamine-N,N,N',N '',N ''-pentaacetic acid, H(3)DTPA-BMA: 2,2'-[(carboxymethyl)imino]bis[ethylenebis(methylcarbamoyl-methyl)imino] diacetic acid} have also been determined under similar conditions. The stability constants (log K-ML) of the complexes of BOPTA and DTPA are very similar, but in 0.15 m NaCl the protonation constants of the ligands (log K-j(H)) and the log K-ML values are lower than those obtained in 0.1 M KCl or Me4NCl by 0.3-0.9 log K units. The order of selectivity of the ligands for Gd3+ over Zn2+ is BOPTA > DTPA > DTPA-BMA. The complex [Cu(DTPA-BMA)](-) deprotonates in the pH range 7-10 with the dissociation of an amide NH group and the coordination of the amide N atom. The kinetics of the exchange/transmetallation reactions between the complex [Gd(BOPTA)](2-) and the metal ions Cu2+, Zn2+, and Eu3+ have been studied by spectrophotometry (Cu2+, Eu3+) and relaxometry (Zn2+) in the pH range 3.3-6 at 25 degrees C in 0.15 m NaCl. The reactions with Cu2+ and Zn2+ occur predominantly with direct attack of the metal ions on the [Gd(BOPTA)](2-) complex. The kinetic activity of Eu3+ is lower, and in the exchange reactions with Eu3+ the proton-assisted dissociation of [Gd(BOPTA)](2-) (which is followed by fast reaction between the free ligand and Eu3+) could be also investigated. The rate constants, characterizing the proton-assisted dissociation of [Gd(BOPTA)](2-) and the exchange reactions occurring with the direct attack of Cu2+, Zn2+, and Eu3+ on the complex, are lower by about 30-90% than the rate constants obtained earlier for similar transmetallation reactions of [Gd(DTPA)](2-). The half-time for the dissociation of [Gd(BOPTA)](2-) at pH 7.4 and at 25 degrees C in the presence of 1 x 10(-5) m Zn2+ and 1 x 10(-5) M Cu2+ is 169 h.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Lanthanides
Thermodynamics
Kinetics
Reaction mechanisms
mri contrast agents
diethylenetriaminepentaacetic acid
stability
ions
dissociation
dimeglumine
constants
biodistribution
thermodynamics
gadopentetate
Megjelenés:European Journal of Inorganic Chemistry. - 13 (2010), p. 1948-1956. -
További szerzők:Pálinkás Zoltán (1984-) (vegyész) Uggeri, Fulvio Brücher Ernő (1935-) (vegyész)
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4.

001-es BibID:BIBFORM002545
Első szerző:Baranyai Zsolt (vegyész)
Cím:Kinetics of the Formation of [Ln(DOTAM)]3+ Complexes / Zsolt Baranyai, István Bányai, Ernő Brücher, Róbert Király, Enzo Terreno
Dátum:2007
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Macrocyclic ligands
Lanthanides
Kinetics
Reaction mechanisms
Megjelenés:European Journal Inorganic Chemistry. - 23 (2007), p. 3639-3645. -
További szerzők:Brücher Ernő (1935-) (vegyész) Király Róbert (1947-) (vegyész) Terreno, Enzo Bányai István (1953-) (vegyész)
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DOI
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5.

001-es BibID:KLTEbibl002358
Első szerző:Brücher Ernő (vegyész)
Cím:Carbonate Exchange for the Complex UO2(CO3)4-3 in Aqueous Siolution as Studied by 13C NMR Spectroscopy / Brücher E., Glaser, J., Tóth I.
Dátum:1991
Megjegyzések:TTK
Tárgyszavak:Kémia
Megjelenés:Inorg. Chem. - 30 (1991), p. 2239-2241.
További szerzők:Glaser, Julius Tóth Imre (1950-) (vegyész)
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6.

001-es BibID:KLTEbibl002357
Első szerző:Brücher Ernő (vegyész)
Cím:Synthesis, Equilibrium, and Kinetic Properties of the Gadolinium(III) Complexes of Three Triazacyclodecanetriacetate Ligands / E. Brücher, S. Cortes, F. Chavez, A. D. Sherry
Dátum:1991
ISSN:0020-1669 1520-510X
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Megjelenés:Inorganic Chemistry. - 30 : 9 (1991), p. 2092-2097. -
További szerzők:Cortes, S. Chavez, F. Sherry, A. Dean
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7.

001-es BibID:KLTEbibl000519
Első szerző:Brücher Ernő (vegyész)
Cím:Kinetics of formation and dissociation of the 1,4,7-triazacyclononane-N,N',N"-triacetate complexes of cerium(III), gadolinium(III), and erbium(III) ions / Ernő Brücher, A. Dean Sherry
Dátum:1990
ISSN:0020-1669
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Megjelenés:Inorganic Chemistry. - 29 : 8 (1990) p. 1555-1559. -
További szerzők:Sherry, A. Dean
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8.

001-es BibID:BIBFORM096827
Első szerző:Burai László
Cím:Formation and Dissociation Kinetics of the Complexes Gd(DOTP)5? and Gd(DOTPMB)? / László Burai, Róbert Király, István Lázár, Ernő Brücher
Dátum:2001
ISSN:1434-1948
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Megjelenés:European Journal Of Inorganic Chemistry. - 2001 : 3 (2001), p. 813-820. -
További szerzők:Király Róbert (1947-) (vegyész) Lázár István (1959-) (vegyész) Brücher Ernő (1935-) (vegyész)
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9.

001-es BibID:bibEBI00008428
Első szerző:Burai László
Cím:Synthesis, potentiometry, and NMR studies of two new 1,7-disubstituted tetraazacyclododecanes and their complexes formed with lanthanide, alkaline earth metal, Mn2+, and Zn2+ ions / L. Burai, J. Ren, Z. Kovács, E. Brücher, A. D. Sherry
Dátum:1998
ISSN:0020-1669
Megjegyzések:Two new 1,7-disubstituted-1,4,7,10-tetraazacyclododecane ligands, DO2P and DO2PME, and their complexes with Mg2+, Ca2+, Sr2+, Mn2+, Zn2+ and Ln3+ were prepared and characterized by pH potentiometry. The pH titration data showed that DO2P and DO2PME both form 1:1 M:L complexes with all divalent and trivalent metal ions. Protonated complexes did not appear to form with the bis(phosphonate ester) ligand, DO2PME, but were evident for all of the metal ion?DO2P complexes. The alkaline earth metal ion?DO2P complexes formed both ML and MHL complexes while the lanthanide ion (Ln3+), Zn2+, and Mn2+ complexes of DO2P formed ML, MHL, and MH2L species. Zn2+ formed the most stable complex with both ligands. The stability (β101) of the LnDO2PME+ complexes increased by about 2 orders of magnitude along the lanthanide series (La3+ to Lu3+) while the stability of the LnDO2P- complexes over this same series increased by over 3 orders of magnitude. The bis(phosphonate) ligand, DO2P, and some of its complexes formed with Ln3+ ions were further examined by NMR spectroscopy. 1H and 31P spectra of DO2P collected as a function of pH provided evidence that the first two protonations on the ligand take place largely at the tertiary nitrogens. The similarity of the 31P chemical shifts of EuDO2P- and EuDOTP5- indicate that DO2P forms an ?in-cage" complex with Eu3+ using all four macrocyclic ring nitrogens and the two phosphonate sidearms as ligands. 17O NMR shifts of the water signal indicated that the DyDO2P- complex has two inner-sphere coordinated water molecules. In the presence of excess of DO2P, a 1:2 metal:ligand, LnDO2P(HDO2P)4-, complex forms with the second ligand interacting only weakly with the coordination sites left vacant by the first DO2P. Both water proton relaxivity data for GdDO2P- and 31P NMR spectra of EuDO2P- provide evidence for formation of an ?out-of-cage" LnH2DO2P+ complex at low pH values (<6.5) in which the two phosphonate groups of DO2P are only involved in bonding with the lanthanide cation.
Tárgyszavak:idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Inorganic Chemistry. - 37 : 1 (1998), p. 69-75. -
További szerzők:Ren, Jimin Kovács Zoltán Brücher Ernő (1935-) (vegyész) Sherry, A. Dean
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10.

001-es BibID:KLTEbibl000520
Első szerző:Cortes, S.
Cím:Potentiometry and NMR Studies of 1,5,9-Triazacyclododecane-N,N',N''-triacetic Acid and its Metal Ion Complexes / S. Cortes, E. Brücher, C. F. G. C. Geraldes, A. D. Sherry
Dátum:1990
ISSN:0020-1669
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Megjelenés:Inorganic Chemistry. - 29 : 1 (1990), p. 5-9. -
További szerzők:Brücher Ernő (1935-) (vegyész) Geraldes, Carlos Frederico de Gusmão Campos Sherry, A. Dean
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11.

001-es BibID:BIBFORM006199
Első szerző:Kálmán Ferenc K. (vegyész)
Cím:Stability constants and dissociation rates of the EDTMP complexes of Samarium(III) and Yttrium(III) / Kalman, F. K., Kiraly, R., Brucher, E.
Dátum:2008
Megjegyzések:The stability constants of Sm(EDTMP) (log K-ML = 20.71) and Y(EDTMP) (log K-ML = 19.19) were determined by a competition reaction between the Ln(3+) ion (Ln(3+) = Sm3+ or Y3+) and Cu2+ for the EDTMP ligand by spectrophotometry at pH approximate to 10, in the presence of an excess amount of citrate (0.15 M NaCl, 25 degrees C). For determining the stability constants of Cu(EDTMP) (log K-ML = 19.36) and Ca(EDTMP) (log K-ML = 8.71) pH-potentiometry was used. In the pH range 4-9 the EDTMP complexes are present in the form of nonprotonated and mono-, di- and triprotonated species. The Ca2+ ion forms a dinuclear complex with Ln(EDTMP). In a simplified blood plasma model consisting of Sm3+, Ca2+ and Zn2+ metal ions, EDTMP, citrate, cysteine and histidine ligands, Sm3+ is practically present in the form of [Sm(HEDTMP)Ca](2-), whereas Zn2+ predominantly forms [Zn(HEDTMP)](5-) and [Zn(H2EDTMP)](4-) complexes. For studying the dissociation rates of the complexes, the kinetics of the metal exchange (transmetallation) reactions between the Ln(EDTMP) complexes and Cu2+-citrate were investigated in the pH range 7-9 by the stopped-flow method. The rates of the exchange reactions are independent of the Cu2+ concentration and increase with the H+ concentration. The rate constants, characterizing the proton-assisted dissociation of the Ln(EDTMP) complexes, are several orders of magnitude higher than those of the similar Ln(EDTA) complexes, because the protonation constants of Ln(EDTMP) are high and the protonated Ln(HEDTMP) and Ln(H2EDTMP) species are present in higher concentration. The half-times of dissociation of Sm(EDTMP) and Y(EDTMP) at pH = 7.4 and 25 degrees C are 4.9 and 7.5 s, respectively. These relatively short dissociation half-time values do not predict the deposition of Ln(3+) ions in bones in the form of intact Ln(EDTMP) complexes. It is more probable that sorption of the EDTMP ligand and Sm3+ or Y3+ ions occurs independently after the dissociation of complexes.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:European Journal Of Inorganic Chemistry. - 30 (2008), p. 4719-4727. -
További szerzők:Király Róbert (1947-) (vegyész) Brücher Ernő (1935-) (vegyész)
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12.

001-es BibID:BIBFORM006198
Első szerző:Kálmán Ferenc K. (vegyész)
Cím:Synthesis, potentiometric, kinetic, and NMR studies of 1,4,7,10-tetraazacyclododecane-1,7-bis(acetic acid)-4,10-bis(methylenephosphonic acid) (DO2A2P) and its complexes with Ca(II), Cu(II), Zn(II) and lanthanide(III) ions / Kalman, F. K., Baranyai, Z., Toth, I., Banyai, I., Kiraly, R., Brucher, E., Aime, S., Sun, X., Sherry, A. D., Kovacs, Z.
Dátum:2008
ISSN:0020-1669
Megjegyzések:A cyclen-based ligand containing trans-acetate and trans-methylenephosphonate pendant groups, H(6)DO2A2P, was synthesized and its protonation constants (12.6, 11.43, 5.95, 6.15, 2.88, and 2.77) were determined by pH-potentiometry and H-1 NMR spectroscopy. The first two protonations were shown to occur at the two macrocyclic ring N-CH2-PO32- nitrogens while the third and fourth protonations occur at the two phosphonate groups. In parallel with protonation of the two -PO32- groups, the protons from the NH+-CH2-PO32- are transferred to the N-CH2-COO- nitrogens. The stability constants of the Ca2+, Cu2+, and Zn2+ (ML, MHL, MH2L, and M2L) complexes were determined by direct pH-potentiometry. Lanthanide(III) ions (Ln(3+)) form similar species, but the formation of complexes is slow; so, "out-of-cell" pH-potentiometry (La3+, Eu3+, Gd3+, Y3+) and competitive spectrophotometry with Cu(II) ion (Lu3+) were used to determine the stability constants. By comparing the log K-ML values with those of the corresponding DOTA (H(4)DOTA = 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) and DOTP (H8DOTP = 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetramethylenephosphonic acid) complexes, the order DOTA < DO2A2P < DOTP was found for all the metal ion complexes examined here with the exception of the Ca2+ complexes, for which the order is reversed. The relaxivity of Gd(DO2A2P) decreases between pH 2 and 7 but remains constant in the pH range of 7 < pH < 12 (r(1) = 3.6 mM(-1) s(-1)). The linewiths of the O-17 NMR signals of water in the absence and presence of Gd(DO2A2P) (at pH = 3.45 and 8.5) between 274 and 350 K are practically the same, characteristic of a q = 0 complex. Detailed kinetic studies of the Ce3+ and Gd3+ complexes with DO2A2P showed that complex formation is slow and involves a high stability diprotonated intermediate Ln(H(2)DO2A2P)*. Rearrangement of the diprotonated intermediate into the final complex is an OH- assisted process but, unlike formation of Ln(DOTA) complexes, rearrangement of Ln(H(2)DO2A2P)* also takes place spontaneously likely as a result of transfer of one of the protons from a ring nitrogen to a phosphonate group. The order of the OH- assisted formation rates of complexes is DOTA > DO2A2P > DOTP while the order of the proton assisted dissociation rates of the Gd3+ complexes is reversed, DOTP > DO2A2P > DOTA. H-1 and C-13 NMR spectra of Eu(DO2A2P) and Lu(DO2A2P) were assigned using two-dimensional correlation spectroscopy (2D COSY), heteronuclear multiple quantum coherence (HMQC), heteronuclear chemical shift correlation (HETCOR), and exchange spectroscopy (EXSY) NMR methods. Two sets of H-1 NMR signals were observed for Eu(DO2A2P) characteristic of the presence of two coordination isomers in solution, a twisted square antiprism (TSAP) and a square antiprism (SAP), in the ratio of 93% and 7%, respectively. Line shape analysis of the H-1 NMR spectra of Lu(DO2A2P) gave lower activation parameters compared to La(DOTP) for interconversion between coordination isomers. This indicates that the Ln(DO2A2P) complexes are less rigid probably due to the different size and spatial requireents of the carboxylate and phosphonate groups.
Tárgyszavak:Természettudományok Kémiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Inorganic Chemistry. - 47 : 9 (2008), p. 3851-3862. -
További szerzők:Baranyai Zsolt (1977-) (vegyész) Tóth Imre (1950-) (vegyész) Bányai István (1953-) (vegyész) Király Róbert Brücher Ernő (1935-) (vegyész) Aime, Silvio Sun, Xiankai Sherry, A. Dean Kovács Zoltán
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